Finasteride and minoxidil in one product: what are the combinations sold abroad (tablet, spray, shampoo), and what can they do?

I'm studying to become a cosmetologist, and because of my own hair loss I've used minoxidil for 4 years, finasteride for 3. I wrote this article because the two are also sold together abroad, in tablet, spray and shampoo form, and it's hard to tell from product pages which is which.

The short answer: it exists, but not the way a factory-made medicine does. Two concepts are worth separating. A licensed (branded) medicine is one that a medicines authority has authorised for sale with a fixed composition and an approved patient information leaflet. A compounded product is one that a pharmacy mixes for a specific patient, on a doctor's prescription. The EU's medicinal products directive states that it doesn't apply to compounded medicines, meaning these have no marketing authorisation1. The US medicines authority (FDA) describes the same thing this way: compounded drugs aren't FDA-approved, which means the FDA hasn't evaluated their safety, effectiveness and quality before they reach the market2.

The foreign finasteride-minoxidil combinations I found are almost all compounded products, or the company itself states they contain an unlicensed drug. The exception is a few Indian factory-made solutions. What you can take from this: if you see a combined product on a site, look for its status in the product description (compounded, unlicensed), because that's what tells you whether this specific composition has been authorised by a regulator.

The compositions below are from September 2026, from the companies' own sites3, and Manual's tablet is from the company's staff's own 2025 paper4. These pages are sources for what's sold, not for the effect.

Keeps' product called “Topical Finasteride and Minoxidil” didn't have a concentration on its listing, so it's not in the table3. Two things stand out from the table. There's no uniform “combined tablet”: alongside finasteride, Happy Head's capsule has 1.25 mg minoxidil, Manual's tablet has 2.5 mg, and Hims says in its leaflet that it tailors the ingredients to the prescription. The licensed, factory-made finasteride tablet approved for hair loss is 1 mg5. And the sprays aren't the same either: Hims and Ro list 0.3% finasteride and 6–7% minoxidil, Numan lists 0.1% finasteride and 10% minoxidil with azelaic acid, and several products have a third or fourth active ingredient (ketoconazole, tretinoin, biotin).

India also sells a factory-made combination, as a topical solution. According to one Indian online pharmacy's listing, Intas's Morr F 5% solution contains 5% minoxidil and 0.1% finasteride, on prescription, and the same page lists further brands for this same pairing, such as Tugain, Coverit, Hair 4U F, Minokem-F and Tricosilk F6. A 2023 Indian paper, two of whose five authors are Glenmark employees, states that a factory-made combination of 5% minoxidil and 0.1% finasteride (Inbilt F) launched in India in 20207. I couldn't find an Indian factory-made combined tablet in a verifiable source.

In Europe I found compounded pharmacy mixtures. One Italian pharmacy's 100 ml solution contains 3 g minoxidil and 0.2 g finasteride (that's 3% and 0.2%), with propylene glycol and ethanol as solvents, and the pharmacy states it's a compounded product requiring a doctor's prescription. One Spanish pharmacy offers an oral capsule on prescription, with compositions of 2.5 mg minoxidil and 1 mg finasteride, 5 mg and 1 mg, or 2.5 mg and 0.5 mg. Another Spanish pharmacy states that some prescriptions combine minoxidil with finasteride or dutasteride, and that the composition must appear on a valid prescription from a doctor registered in Spain8. What you can take from this: the same name can mean a different composition at each company and pharmacy, so two “finasteride-minoxidil sprays” or “combined tablets” aren't interchangeable.

Not in the registers I reviewed. Neither finasteride nor minoxidil appears in the European Medicines Agency's (EMA) list of centrally authorised medicines, because these products are authorised country by country9. So I also checked the national databases. The Spanish authority's database has 22 minoxidil and 53 finasteride products, including a prescription-only finasteride scalp spray, Alocare, but not a single one containing both together10. The French public medicines database has 28 finasteride and 19 minoxidil products, no combination at all11. In Hungary, the medicine finder that mirrors the official master data only showed standalone finasteride and minoxidil products; I couldn't query the authority's own database directly, so I'll put it this way: I found no combined product12. I couldn't download the Italian database, so I didn't check the absence of a combination there.

In 2021, an expert committee of India's medicines authority asked a company for a fresh submission for a lotion application containing 5% minoxidil and either 0.25% or 0.5% finasteride, and one point in the reasoning read: “Proposed higher strengths of Finasteride are not approved anywhere else in the world.”13 I couldn't find the authorisation document for the two-component combination of 5% minoxidil and 0.1% finasteride on the authority's site.

On its own, without minoxidil, there is a licensed scalp spray with finasteride: Fynzur in Hungary, Alocare in Spain. What this can do compared to the tablet, I wrote about in the article on topical finasteride. On using it together with minoxidil, Fynzur's Hungarian Summary of Product Characteristics states: “No data are available on the concurrent use of Fynzur spray with 1 mg oral finasteride or with topical minoxidil for male pattern hair loss.”14

What holds true for every European reader from this: not a single authority in the European registers I reviewed has approved a combined finasteride-minoxidil product, and the rules for pharmacy compounding and online medicine ordering differ by country. I found no regulatory explanation for why there's no such factory-made product. What you can take from this: if you see a combined product in Europe, it's very likely a pharmacy's or a company's mixture, and this combined composition hasn't been evaluated by a regulator.

This section covers studies where participants received finasteride and minoxidil together, applied to the scalp, mostly mixed into one product, and every study compared the combination against minoxidil alone. So the question is always whether adding finasteride gave anything on top of minoxidil.

In Tanglertsampan's 2012 Thai study, 40 men took part for 24 weeks, double-blind, meaning neither the participants nor the investigators knew who got what. A mixture of 3% minoxidil and 0.1% finasteride was compared with 3% minoxidil alone. There was no difference between the two groups in hair count change; the mixture was better on the pooled photographic assessment, and no sexual side effect was reported15.

In Suchonwanit and colleagues' 2018 Thai study, 40 men aged 18 to 60 used a mixture of 0.25% finasteride and 3% minoxidil, or 3% minoxidil alone, twice daily for 24 weeks, double-blind. The mixture was significantly better in hair density, shaft thickness and photographic assessment (statistically significant means the difference is unlikely to be down to chance)16. The “about 90%” in the abstract is the share of those on the mixture who saw moderate or marked improvement; that's a within-group share, not the difference between the two groups.

In Bharadwaj and colleagues' 2023 Indian study, there were 60 men in three groups of twenty, over 24 weeks, open-label, meaning both the participants and the investigators knew who got what. A mixture of 5% minoxidil and 0.25% finasteride was compared against 5% minoxidil and 0.25% finasteride solution separately. In total hair density, no group was better than the others at week 12; by week 24 the mixture was better; in the density of thick, terminal hairs the mixture was already better at week 12. In the physician and patient assessments, both the mixture and minoxidil were better than the finasteride solution, and the abstract doesn't report a difference between the mixture and minoxidil on this. Flaking and itching were reported with both the mixture and minoxidil17.

In Asad and colleagues' 2024 Pakistani study, 164 men aged 30 to 60 took part for 12 weeks, single-blind, meaning only one of the two sides didn't know who got what. A mixture of 0.25% finasteride and 5% minoxidil was compared against 5% minoxidil alone. “Efficacy” was 86.7% with the mixture and 69.1% with minoxidil; what the authors meant by efficacy isn't clear from the abstract18.

In Lubis and colleagues' 2025 Indonesian study, 40 men used a mixture of 0.1% finasteride and 5% minoxidil, or 5% minoxidil alone, for 12 weeks. Hair density and shaft thickness increased from baseline in both groups, with no difference between the two groups, meaning the mixture did as much as minoxidil alone. As systemic side effects, those on the mixture reported mild erectile dysfunction and chest pain, the minoxidil group reported reduced libido, and one participant on the mixture developed contact dermatitis19.

Rossi and Caro's 2024 Italian study stands apart, because there the two drugs weren't in one bottle. 42 men, average age 24, took part for 6 months. One group (19 people) used 5% minoxidil in the morning and finasteride spray in the evening, a second (12 people) used only the spray, and a third (11 people) used only minoxidil twice daily. The average increase in hair density was greatest in the group using both together, but this difference was only significant compared with the spray-only group, not compared with the minoxidil-only group. It was better than both other groups on photographic assessment, and the share reaching at least 2 points on the scale was also the largest in this group after both 3 and 6 months (the reported shares in order: 79%, 8% and 41%); there was no difference between the three groups in shaft thickness or hormone levels20. The groups are small, between 11 and 19 people.

Li and colleagues' 2025 meta-analysis (a meta-analysis statistically pools the results of several studies) included 7 randomised trials, 396 men in total, with 3–5% minoxidil and 0.1–0.25% finasteride, for 3–6 months, and minoxidil was the control in every one. They reported three main pooled endpoints (hair density, shaft thickness, photographic score), and all three favoured the mixture. For hair density, data from 5 studies with 170 participants (their own summary table says 180) gave an average difference of 9.22 hairs per square centimetre, with a 95% confidence interval of 0.29 to 18.1621. The confidence interval is the range within which the true difference very likely lies based on the measurement; here the lower edge nearly touches zero, so this result sits at the statistical borderline. Pooling 3 studies gave an average difference of 2.26 in shaft thickness (0.68 to 3.83; the paper doesn't state the unit), and 0.79 points in photographic score from 3 studies (0.50 to 1.08), and both of these were clearly significant21. The authors rated the reliability of the evidence on the international GRADE scale: moderate for hair density, low for shaft thickness and photographic score, and their conclusion is that the mixture applied to the scalp is more effective than minoxidil alone21.

The limitations, from the same study: there was substantial variation between the studies for hair density (the I² measure for this was 90%), mainly, per the authors, because of a single outlier study, excluding which brought the variation down to low (12%); by the authors' own risk assessment, the assessor knew who got what in several studies; and the Rossi study, where the two drugs went in two separate products, is also part of the pooled shaft thickness and photographic score results21.

There are two things I don't carry over from this paper. Its discussion section states that no sexual side effect was reported for the mixture across the included studies21, yet the included Lubis study's abstract states: “Systemic SEs included libido reduction (control), mild erectile dysfunction, and chest pain (treatment).”, meaning mild erectile dysfunction and chest pain were reported for those on the mixture19. And it counted the Rossi study among the seven as a mixture, even though there the two drugs went in two separate products, at two different times of day20. Of the remaining six, in three the title or text says the two drugs were mixed into one product (Tanglertsampan, Suchonwanit, Bharadwaj), for two (Asad, Lubis) the abstract doesn't detail this, and I didn't read the sixth (Sheikh 2015).

Overall: every study compared the mixture against minoxidil alone. The meta-analysis, pooled, favoured the mixture, with low to moderate certainty. The picture is more mixed in the individual studies: of the five mixture studies described here (not counting Rossi's), four had the mixture better on some assessment, but in the Tanglertsampan study there was no difference in hair count, and in the Lubis study nothing at all after 12 weeks. Where there was no difference, the mixture did as much as minoxidil alone. The authors themselves write that because the studies lasted at most 6 months, they don't speak to the long-term effect21. What you can take from this: there's little, small (40–164 person) and short (12–24 week) evidence on the applied mixture, and none of it followed participants for years.

Not the same. The mixtures studied contained 0.1–0.25% finasteride and 3–5% minoxidil21, while two American telehealth companies (services offering an online medical consultation followed by a prescription and product by mail), Hims and Ro, sell a spray with 0.3% finasteride and 6–7% minoxidil, and the UK's Numan sells 0.1% finasteride and 10% minoxidil, with azelaic acid3. I couldn't find a controlled study on these exact compositions. I also couldn't calculate how many micrograms of finasteride are in one spray, because the companies don't state the amount per spray.

There's also real-world usage data on the products you can buy, though none of it is a randomised trial. Yu and colleagues in 2026 published data from the Hims & Hers platform: between April 2021 and April 2025, 638,629 men were prescribed a compounded, scalp-applied finasteride-minoxidil product, 151,352 (23.7%) completed the roughly 130-day follow-up survey, and among them 80.4% were satisfied and 2.7% reported a side effect. Four of the authors are full-time company employees, two are consultants, and they themselves write that the retrospective data and the lack of a control group rule out any causal conclusion22. Abeck and colleagues in 2024 studied 1545 patients on the mixture at a German online dermatology platform: 238 (15.4%) completed the 6-week survey, and 11.8% of them reported a treatment-related side effect. Compared with those on the tablet finasteride, fewer stuck with the treatment, there were more local side effects, no difference in the frequency of sexual side effects, and the authors' summary is that the mixture seems effective and well tolerated, but no better than the tablet23.

There's a dataset from India too. Kerure and colleagues in 2023 retrospectively compared the factory-made 5% minoxidil solution and the 5% minoxidil plus 0.1% finasteride combination in 261 patients at 66 Indian clinics: after 16 weeks, marked or excellent improvement on physician assessment was 52% with minoxidil and 68% with the combination. The study was a retrospective data analysis, without randomisation, the paper doesn't report a statistical comparison between the two groups, and two of its five authors are Glenmark employees7. What you can take from this: these datasets were done without randomisation; the Yu and Abeck ones report satisfaction and reported complaints, the Kerure one reports physician assessment. The composition of the Indian factory-made solution (5% minoxidil, 0.1% finasteride) was tested with a control group by the Lubis study, and found no difference from minoxidil after 12 weeks19; the Kerure solution is alcohol-free, in a so-called cetosomal vehicle, the Lubis one isn't specified in the abstract, and the Kerure dataset ran 16 weeks. I couldn't find a controlled measurement for the Hims and Ro sprays' composition (0.3% finasteride, 6–7% minoxidil).

The measurements say no, not only there. Finasteride reduces the production of the hormone DHT (dihydrotestosterone); I wrote about this and its role in hair loss in the parent article. In Suchonwanit's 2018 study in men, with twice-daily use of the mixture containing 0.25% finasteride, blood DHT fell by roughly 5% over 24 weeks, and no systemic side effect was reported16. In a 2019 study with the same mixture, in 30 postmenopausal women, serum DHT fell significantly from baseline, and the authors wrote that because it can be absorbed through the skin, the mixture should be reserved for postmenopausal women24. In the large study of the licensed, finasteride-only spray, in 458 randomised men, serum DHT fell 34.5% with the spray and 55.6% with the tablet over 24 weeks25. The FDA's 2025 text states that finasteride reaching the blood through the skin is “expected”2.

So absorption depends on the concentration, the vehicle and the amount applied, and the 0.3% in the Hims and Ro sprays doesn't match any of the mixtures measured. What you can take from this: the applied form may carry a smaller systemic effect than the tablet, but the tablet's side-effect list can't be crossed off for it either.

In April 2025, the American medicines authority issued a warning to health care providers, pharmacies and consumers about compounded, scalp-applied finasteride. The text states that the FDA is aware of pharmacies and telemedicine platforms selling finasteride alone or mixed with another active ingredient, such as minoxidil, for hair loss, and that there's no FDA-approved topical finasteride product in the US2.

32 such cases were reported to the authority's adverse event database between 2019 and 2024. Per the FDA, the reported complaints match those reported for the factory-made, oral finasteride: erectile dysfunction, anxiety, suicidal ideation, brain fog, depression, fatigue, insomnia, reduced libido and testicular pain. Most of the reports received said the complaints persisted even after stopping the drug, and in some cases the prescriber told the patient that because the drug is topical, there's no side-effect risk. The FDA also lists local reactions (irritation, redness, dryness, flaking, stinging and burning), and notes the applied drug can transfer to others, especially women. It also states that factory-made finasteride products are contraindicated in pregnancy, because they may cause developmental abnormalities of a male fetus's genitals in a pregnant woman; that women shouldn't handle a broken or crushed finasteride tablet, because the active substance may be absorbed; and that the factory-made tablet's coating protects against contact if the tablet isn't broken or crushed, while the compounded, scalp-applied products have no coating2.

The 32 cases are voluntary reports: there's no denominator, so it isn't known how many users they came from, meaning they give no frequency, and they don't only concern combined products. Using this same database, Gupta and colleagues' 2026 analysis also found a signal for post-finasteride-like side effects with topical finasteride, though less often than with the tablet, and the authors call for caution in stating causation26. I wrote about post-finasteride syndrome, meaning complaints that persist even after stopping the drug, in the parent article.

A regulatory review concluded in the European Union in 2025. The drug safety letter, issued in agreement with the EMA and the Hungarian authority, states that suicidal ideation is a side effect linked to oral finasteride products, mainly reported in patients treated for hair loss. 313 such cases were reported in connection with finasteride in the European database, and per the letter this should be read against an estimated roughly 270 million patient-years of use (a patient-year shows how many people used it for how many years combined); the frequency can't be established from the available data. On topical finasteride, the letter states that there currently isn't enough evidence to confirm a causal link5.

For oral finasteride, the letter asks that anyone experiencing low mood, depression or suicidal ideation stop treatment and see a doctor5. For topical finasteride, the letter states that its label already includes information about the mood-related risk of the oral form5, and Fynzur's Summary of Product Characteristics states that patients must be told to see a doctor if they experience any psychiatric symptom14. A compounded mixture has no regulator-approved patient information leaflet2.

The largest randomised study described here on using the two together involves two separate products: an oral finasteride tablet and minoxidil applied to the scalp. In Hu and colleagues' 2015 Chinese study, 450 men were randomly split into three groups (160, 130 and 160 people), 428 were evaluated, over 12 months. One group took 1 mg finasteride daily, the second applied 5% minoxidil, the third used both. After 12 months, improvement was seen in 80.5% of men on finasteride, 59% on minoxidil, and 94.1% on both together. Side effects were rare (finasteride 1.8%, minoxidil 6.1%), and disappeared immediately after stopping the drug27. The limitations: the abstract doesn't say whether the assessment was blinded or what counted as improvement, and the combined group's side-effect rate isn't given.

Khandpur and colleagues' 2002 Indian study with 100 men, over one year, open-label, compared four groups: finasteride tablet alone, finasteride plus 2% minoxidil solution, minoxidil alone, and finasteride with ketoconazole shampoo. Hair grew in every group; the best result came from finasteride and minoxidil together, followed by finasteride with ketoconazole, then finasteride alone, then minoxidil alone; the ketoconazole group had 10 people28. No group got all three together, what hair loss forums call the “Big 3”. Chen and colleagues' 2020 meta-analysis pooled 5 randomised trials; all five compared the combination against minoxidil, only two against finasteride alone. The combined group was better on photographic assessment, more had marked improvement, and fewer had worsening or no change, while there was no significant difference in hair density change or side effects compared with those on minoxidil or finasteride alone. The authors' conclusion is that the combination is more effective, with similar safety29. I couldn't access this paper's full text, so I also don't know whether the included studies used oral or topical finasteride.

What you can take from this: the largest randomised study described here on using the two together, 450 people, used two separate products, and its result can't be carried over one-to-one to a mixed product.

I couldn't find a controlled study. Searching the scientific database (Europe PMC) for oral minoxidil, finasteride and randomised trial together returned only two reviews. Two papers come close.

Johnson and colleagues' 2025 UK paper covers the online provider Manual's “All-in-One” tablet, containing 1 mg finasteride and 2.5 mg minoxidil in one tablet. They looked back at data from 502 men between 2020 and 2023 who stuck with treatment for roughly 12 months, based on their own self-taken photos. 92.4% had stable or improved hair, 57.4% were rated as improved, meaning a score above zero on the minus 3 to plus 3 scale; the authors call this “marked improvements”, even though on their own scale “marked improvement” is plus 3. The limitations are serious: no control group, agreement between photo assessors was poor (in the authors' own words, “fair to slight”), no side-effect questionnaire or lab test was taken, those who'd stopped treatment earlier were excluded, and all five authors are company employees4.

Nohria and colleagues in 2025, in a short research letter, compared low-dose oral minoxidil alone with treatment combined with finasteride or dutasteride. I only had access to this paper's title, not its content, so I don't quote a result from it30.

The composition of combined tablets differs by company (minoxidil is 1.25 mg in Happy Head's capsule, 2.5 mg in Manual's tablet, and Hims tailors it to the prescription), meaning one paper's result wouldn't carry over to the others even if it were controlled. Ask your doctor this if it comes up: what study do you know of for each ingredient, and how do you monitor minoxidil's effect on the heart and circulation?

There's a documented Spanish example of this, though with minoxidil alone. Moreno-Arrones and colleagues, in 2022, described 12 women (aged 25 to 73, between 2018 and 2020) who were prescribed a compounded 0.5–1 mg minoxidil capsule for hair loss. Six fainted from a drop in blood pressure, six developed general oedema (fluid retention), one patient had a stroke, one a heart attack. According to independent laboratory testing of the capsules, every one of them received a larger dose than prescribed because of a mixing error, according to the text, between 50 and 1000 mg per capsule. Every one of them made a full recovery. According to the authors, around 1,700 prescriptions were issued in the period, putting the rate of severe cases at 0.7%.31 The limitations: the letter's table also lists a figure of 48 mg, and for seven patients it only states how many times the prescribed dose they received (20 to 100 times for six, 50 to 200 times for one), so the real lower bound could be below 50 mg; and the 0.7% denominator is an estimate.

The same Spanish group stated in 2024 that in their severe side-effect cases the medicine was always compounded, and that the product sold to the customer had a very significant compositional error, for example up to a hundred times the prescribed dose; with factory-made, marketed oral minoxidil, at the doses used for hair loss, they saw no such severe side effect.32 This is their own clinical experience, not a systematic comparison. So in these cases, patients received a dose many times higher than prescribed because of a mixing error.

There's also a case involving a combined capsule. In 2020, an American pharmacy, MasterPharm, recalled its compounded hair-loss capsule called “Finasteride Plus 1.25mg”, because it contained undeclared minoxidil, in a larger amount than in authorised products, according to the company notice; the company received 33 reports of rapid heartbeat, fluid retention, dizziness and low blood pressure. The notice was published by the FDA on its website.33 I didn't find an independent lab measurement of whether the mixed sprays and capsules on sale actually contain the stated amount. What you can take from this: with a compounded mixture, the accuracy of the dose depends on that particular pharmacy's work, and you can't verify this as a customer.

One of the large datasets described here is Vañó-Galván and colleagues' 2021 multi-centre, retrospective analysis: 1404 patients (two-thirds women, average age 43) who took low-dose oral minoxidil for any kind of hair loss for at least 3 months. The study is about oral minoxidil, not a combined product; whether patients also took something else alongside it isn't clear from the abstract. Because the dose was changed for many, 2469 dose periods were analysed. The most common side effect was unwanted hair growth (15.1%), which led 14 patients (0.5%) to stop. Systemic side effects included dizziness (1.7%), fluid retention (1.3%), rapid heartbeat (0.9%), headache (0.4%), swelling around the eyes (0.3%) and insomnia (0.2%); these led 29 patients (1.2%) to stop, and no life-threatening side effect was seen34. The limitations: no control group, the percentages refer to dose periods, not to patients, and the abstract doesn't report a separate result for using it together with finasteride.

With applied mixtures, scalp dermatitis also comes up. Kiratiwongwan and colleagues' 2025 pooled analysis looked at 99 patients across 46 papers where a patch test (an allergen test using a patch stuck to the skin) confirmed an allergy caused by a minoxidil product: the trigger was minoxidil itself in 74.7% of them, and the solvent propylene glycol in 17.1%35. In an older, 2002 paper, propylene glycol was still the majority trigger among their own tested patients36. I wrote about the side effects of minoxidil applied to the skin in the minoxidil article, and about finasteride's, with the regulatory numbers, in the parent article. What you can take from this: a propylene-glycol-free mixture doesn't mean there'll be no reaction, and the Italian pharmacy solution mentioned above also uses propylene glycol as its solvent.

I couldn't find an approved, medicine-marketed finasteride shampoo; more on this below. A shampoo sold under a hair-loss theme can still be finasteride-free, even if the company also sells finasteride elsewhere. One example I opened myself: Keeps, which also has a scalp product containing finasteride and minoxidil, describes its “Thickening Shampoo” as containing, among other things, biotin, caffeine, green tea and saw palmetto; finasteride isn't listed in its description, and the product page itself states: “It does not treat or stop hair loss. It is not clinically proven to improve hair growth.”37

An American pharmacy (PHC Pharmacy) offers a compounded shampoo containing finasteride, minoxidil and progesterone on prescription; the pharmacy's own product page (viewed 26 September 2026) describes it as a product made to prescription; I don't quote its composition, and I couldn't find a study on its effect38.

I couldn't find a clinical trial on a finasteride, minoxidil or dutasteride shampoo, even with five different search variations. The topical finasteride studies I found all tested a spray or solution left on the scalp; a 2018 systematic review's 7 included papers don't name a shampoo form in any of their titles or abstracts39. The difference is contact time, how long the product stays on the skin. In the large study of the licensed finasteride spray, the protocol read: “The topical spray solution was to be left in place for at least 6-8 h, then washed off with shampoo”, meaning the spray had to be left on the scalp for at least 6–8 hours, and only then washed off with shampoo25. With minoxidil, the UK label for the 5% Regaine solution states that the hair and scalp must be completely dry before applying, 1–2% of the applied dose is absorbed into the body, and in one clinical study the blood level peaked roughly 5.8 hours after applying40. A shampoo stays on the scalp for a few minutes before you rinse it out.

I couldn't find a measurement of how much finasteride or minoxidil would be absorbed in minutes from a shampoo. That less would be absorbed from a shampoo is a conclusion drawn from the shorter contact time, with no measured data behind it, and it doesn't mean such a shampoo is proven ineffective either. What can be said is that the effect measured in the studies is tied to hours of contact.

The EU's cosmetics regulation names minoxidil as prohibited: entry 372 on the list of substances prohibited in cosmetic products, in Annex II41. A minoxidil shampoo therefore can't be marketed as a cosmetic in the EU. The regulation's annexes don't name finasteride by name. Annex II does, however, have a group entry, 390: “Antiandrogens of steroid structure”41; I couldn't find an official ruling on whether this applies to finasteride. I found no shampoo form of finasteride or minoxidil approved as a medicine, either in Hungary or elsewhere; in Hungary, the only licensed topical finasteride product is Fynzur, and that's a spray. I found no regulatory explanation for why there's no finasteride shampoo.

Caffeine is a different case: a 2025 systematic review found that 4 of its 9 included studies used a shampoo42. I wrote about the ketoconazole and caffeine shampoo data in the article on anti-hair-loss shampoos. Check any “DHT blocker” or “finasteride” shampoo for this: the ingredient list instead of the product name, and if it does contain finasteride, whether it's a prescription, pharmacy-compounded product.

Microneedling is a mechanical stimulus with no hormonal effect, so it can be added alongside drugs that act on DHT. The Dermastamp is a fixed 1 mm, at-home device: the needle stimulates the area around the follicle, and doesn't touch DHT through its mechanism. This is inferred from the mechanism, not measured. You don't skip oral finasteride or dutasteride on the day you stamp. With scalp-applied products, stamping day is a pause, and the exact timing differs by product: the timing of actives. For anyone who doesn't want to touch their hormones, this is a route that stays available, with one limitation: in the study measuring the combination, both groups also received minoxidil, and the study used a 1.5 mm clinical roller, not our fixed 1 mm device; there's less data on it used alone. What it can do, what it can't, and who it's not for: I've written it all on its page.

See the Dermastamp